Transmission coil module for wireless power transmitter

ABSTRACT

A transmitting coil module for wirelessly transmitting power, the transmitting coil module including at least one transmission coil having a hollow portion in a center area thereof; a shield disposed below the at least one transmission coil; and a metal sheet disposed below the shield. Further, the shield includes at least one functional hole in a region corresponding to the hollow portion of the at least one transmission coil.

CROSS REFERENCE TO RELATED APPLICATION

This application is a Continuation of co-pending application Ser. No.15/367,925, filed on Dec. 2, 2016, which claims priority under 35 U.S.C.§ 119(a) to Application No. 10-2015-0181030, filed in Republic of Koreaon Dec. 17, 2015, all of which are hereby expressly incorporated byreference into the present application.

TECHNICAL FIELD

Embodiments relate to a wireless power transfer technology, and moreparticularly, to a method of mounting a transmission coil, whichwirelessly transmits power, in a wireless power transmitter.

BACKGROUND

With the recent development of information and communication technology,a ubiquitous society based on information and communication technologyhas arisen.

In order to enable access to and by information sharing applianceswithout regard to time or place, sensors, which incorporate computerchips having a communication function therein, need to be installed inall public facilities. Thus, problems related to the supply of power tothese appliances or sensors have newly arisen. In addition, as the kindsof portable appliances, such as, for example, mobile phones, Bluetoothhandsets, and music players such as iPod, have rapidly increased, thetask of charging a battery demands time and effort on the part of theuser. As a method to solve this problem, a wireless power transfertechnology has recently received attention.

A wireless power transmission (or wireless energy transfer) technologyis a technology that wirelessly transfers electricity from a transmitterto a receiver using the principle of induction of a magnetic field. Anelectric motor or a transformer using the principle of electromagneticinduction has been used since the 1800's, and since that time methods oftransferring electricity by emitting electromagnetic waves such as laseror radio waves have been attempted. Electric toothbrushes or somewireless razors that are often used are actually charged based on theprinciple of electromagnetic induction.

Wireless energy transfer methods that have been achieved thus far may bebroadly divided into a magnetic induction method, an electromagneticresonance method, and an RF transmission method using a short-wavelengthradio frequency.

The magnetic induction method is a technology using a phenomenonwhereby, when two coils are arranged close to each other and current isapplied to one coil, a magnetic flux is generated to generateelectromotive force in the other coil, and the commercialization ofmagnetic induction is quickly progressing in the field of smallappliances such as mobile phones. The magnetic induction method maytransmit power of a maximum of several hundred kilowatts (kW) and mayhave high efficiency. However, since the maximum transfer distance is 1cm or less, an appliance needs to be generally located close to acharger or a substrate.

The electromagnetic resonance method has the feature of using anelectric field or a magnetic field, rather than using electromagneticwaves, current or the like. The electromagnetic resonance method ishardly influenced by an electromagnetic wave, and therefore is harmlessto other electronic appliances or humans. In contrast, theelectromagnetic resonance method may be used at a limited distance andin a limited space, and the energy transfer efficiency thereof issomewhat low.

The short-wavelength wireless power transfer method,—referred to inbrief as an RF transmission method,—uses a method of directlytransmitting and receiving energy in the form of radio waves. Thistechnology is an RF type wireless power transfer method using arectenna. “Rectenna” is a portmanteau of “antenna” and “rectifier”, andmeans an element that directly converts RF power into direct current(DC) power. That is, the RF transmission method is a technology ofconverting alternating current (AC) radio waves into DC radio waves andusing DC radio waves. Recently, research into the commercialization ofRF transmission has been actively conducted as the efficiency thereofhas improved.

Such wireless power transfer technology may be variously used in allindustries, such as, for example, IT, rail, and consumer electronics, inaddition to the mobile industry.

Recently, in order to increase the rate of recognition of a wirelesspower receiver placed on a charger bed, a wireless power transmitter inwhich a plurality of coils is mounted has been launched. The coils needto be located at appropriate positions in order to optimize powertransmission efficiency and to prevent the formation of dead zones, inwhich charging is impossible.

That is, the arrangement and fixing of the coils included in thewireless power transmitter and the electrical connection between thecoils and peripheral circuits are important in determining theperformance of the wireless power transmitter. However, when thearrangement and fixing of the coils and the electrical connection withperipheral circuits are changed due to various factors in the process ofmanufacturing the wireless power transmitter, wireless powertransmission having a desired quality may not be realized.

SUMMARY

Accordingly, embodiments are devised to solve the problems of therelated art described above, and provide a transmission coil module fora wireless power transmitter.

In addition, embodiments provide a transmission coil module for awireless power transmitter, which may maintain a desired quality as theresult of mounting transmission coils in the wireless power transmitterin a modular device.

The technical objects to be accomplished by the embodiments are notlimited to the aforementioned technical objects, and other unmentionedtechnical objects will be clearly understood from the followingdescription by those having ordinary skill in the art.

In one embodiment, a transmission coil module includes a transmissioncoil for wirelessly transmitting power, a coil frame including areceptacle for insertion of the transmission coil, a support unit forsurrounding the receptacle, and a central fixing plate formed inside thereceptacle and corresponding to an inner shape of the transmission coil,and a connector for electrically connecting the transmission coil to acontrol circuit board, wherein the support unit and the central fixingplate are integrally formed with each other.

The coil frame may have an indented side surface, and the connector maybe located in the indented side surface.

The coil frame may further include a lead wire insertion terminal formedin the indented side surface to provide a space into which a lead wireof the transmission coil is fitted.

The connector may be connected to the lead wire, fitted into the leadwire insertion terminal, via soldering using a laser.

The transmission coil module may further include a shield mounted belowthe transmission coil, and a metal sheet mounted below the shield, andthe shield and the metal sheet may be located inside the coil frame.

The shield may be a ferrite sheet.

The metal sheet may include aluminum.

In another embodiment, a transmission coil module includes a firstwireless transmission coil, a second wireless transmission coil and athird wireless transmission coil located below the first wirelesstransmission coil and spaced apart from each other in the same plane, acoil frame including a first receptacle for insertion of the firstwireless transmission coil, a second receptacle for insertion of thesecond wireless transmission coil, a third receptacle for insertion ofthe third wireless transmission coil, a support unit for surrounding thefirst, second and third receptacles, and first, second and third centralfixing plates corresponding to an inner shape of each of the first,second and third wireless transmission coils, and a connector forelectrically connecting the first, second and third wirelesstransmission coils to a control circuit board, wherein the support unit,the first, second and third central fixing plates are integrally formedwith each other.

The embodiments are only some of exemplary embodiments, and variousembodiments in which technical features of the embodiments are reflectedmay be derived and understood based on the following detaileddescription of the embodiments by those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are provided to assist in the understanding ofthe embodiments, and provide the embodiments along with a detaileddescription. However, the technical features of the embodiments are notlimited to particular drawings, and the features illustrated in therespective drawings may be combined with each other so as to configurenew embodiments.

Arrangements and embodiments may be described in detail with referenceto the following drawings in which like reference numerals refer to likeelements and wherein:

FIG. 1 is a view for explaining a detection signal transmissionprocedure in a wireless power transmitter according to an embodiment;

FIG. 2 is a state transition diagram for explaining a wireless powertransfer procedure that is defined in the WPC standard;

FIG. 3 is a state transition diagram for explaining a wireless powertransfer procedure that is defined in the PMA standard;

FIG. 4 is a view for explaining an electromagnetic-induction-typewireless charging system according to an embodiment;

FIG. 5 is a view for explaining the configuration of a transmission coilmodule according to an embodiment; and

FIGS. 6 to 10 are views respectively for explaining a method ofmanufacturing the transmission coil module according to an embodiment.

DESCRIPTION OF SPECIFIC EMBODIMENTS

Hereinafter, an apparatus and various methods, to which the embodimentsare applied, will be described in more detail with reference to theaccompanying drawings. The suffixes “module” and “unit” of elementsherein are used for convenience of description and thus can be usedinterchangeably and do not have any distinguishable meanings orfunctions.

In the following description of the embodiments, it will be understoodthat, when each element is referred to as being formed “on” or “under”the other element, it can be directly “on” or “under” the other elementor be indirectly formed with one or more intervening elementstherebetween. In addition, it will also be understood that “on” or“under” the element may mean an upward direction and a downwarddirection of the element.

In the following description of the embodiments, for convenience ofdescription, an apparatus of wirelessly transmitting power, whichconfigures a wireless power transmission system, may be usedinterchangeably with a wireless power transmitter, a wireless powertransmission apparatus, a transmission terminal, a transmitter, atransmission apparatus, a transmission side, a wireless power transferapparatus, etc. In addition, for convenience of description, anapparatus for wirelessly receiving power from a wireless powertransmission apparatus may be used interchangeably with a wireless powerreception apparatus, a wireless power receiver, a receiver, a receptionterminal, a reception side, a reception apparatus, etc.

A transmitter according to an embodiment may be configured in the formof a pad, a cradle, an Access Point (AP), a small base station or astand, and may be of a ceiling-mounted type or a wall-mounted type. Onetransmitter may transfer power to a plurality of wireless powerreception apparatuses. To this end, the transmitter may include at leastone wireless power transfer unit. Here, the wireless power transfer unitmay use various wireless power transfer standards based on anelectromagnetic induction charging method using the principle ofelectromagnetic induction, in which a power transmission-end coilgenerates a magnetic field so that electricity is induced in areception-end coil under the influence of the magnetic field. Here, thewireless power transfer unit may include an electromagnetic inductiontype wireless charging technology defined by the Wireless PowerConsortium (WPC) and the Power Matters Alliance (PMA), which arewireless charging technology standardization organizations.

In addition, a receiver according to an embodiment may include at leastone wireless power reception unit, and may wirelessly receive power fromtwo or more transmitters at the same time. Here, the wireless powerreception unit may include an electromagnetic-induction-type wirelesscharging technology that is defined by the Wireless Power Consortium(WPC) and the Power Matters Alliance (PMA), which are wireless chargingtechnology standardization organizations.

The receiver according to the embodiment may be used in small electronicappliances, such as, for example, a mobile phone, a smart phone, alaptop computer, a digital broadcasting terminal, a Personal DigitalAssistant (PDA), a Portable Multimedia Player (PMP), a navigationsystem, an MP3 player, an electric toothbrush, an electronic tag, alighting apparatus, a remote controller, a float, and a wearable devicesuch as a smart watch, without being limited thereto, and may be used inother various appliances so long as they allow the installation andbattery charging of the wireless power reception unit according to theembodiment.

FIG. 1 is a view for explaining a detection signal transmissionprocedure in a wireless power transmitter according to an embodiment.

Referring to FIG. 1, three transmission coils 111, 112 and 113 may bemounted in the wireless power transmitter. Each transmission coil mayoverlap at a portion thereof with another transmission coil, and thewireless power transmitter sequentially transmits predetermineddetection signals 117 and 127 for detecting the presence of a wirelesspower receiver (e.g. digital ping signals) in a predefined sequencethrough each transmission coil.

As illustrated in FIG. 1, the wireless power transmitter maysequentially transmit the detection signals 117 via a primary detectionsignal transmission procedure designated by reference numeral 110, andmay identify the transmission coils 111 and 112 that have received asignal strength indicator 116 from a wireless power receiver 115.Subsequently, the wireless power transmitter may sequentially transmitthe detection signals 127 via a secondary detection signal transmissionprocedure designated by reference numeral 120, may identify onetransmission coil that has better power transfer efficiency (or chargingefficiency), i.e. that is more closely aligned with a reception coil,among the transmission coils 111 and 112, which have received a signalstrength indicator 126, and may perform control for power transfer, i.e.wireless charging, through the identified transmission coil.

As illustrated in FIG. 1, the reason why the wireless power transmitterperforms the detection signal transmission procedure two times is tomore accurately identify which transmission coil is the most closelyaligned with the reception coil of the wireless power receiver.

When the first transmission coil 111 and the second transmission coil112 have received the signal strength indicators 116 and 126 asillustrated in the blocks designated by reference numerals 110 and 120of FIG. 1, the wireless power transmitter selects the best-alignedtransmission coil based on the signal strength indicator 126 received byeach of the first transmission coil 111 and the second transmission coil112, and performs wireless charging using the selected transmissioncoil.

FIG. 2 is a state transition diagram for explaining a wireless powertransfer procedure that is defined in the WPC standard.

Referring to FIG. 2, power transfer from a transmitter to a receiverbased on the WPC standard may broadly be divided into a selection phase210, a ping phase 220, an identification and configuration phase 230,and a power transfer phase 240.

A transmitter may transition to the selection phase 210 when aparticular error or a particular event is detected at the time at whichpower transfer begins or while power transfer is maintained. Here, theparticular error and the particular event will become apparent from thefollowing description. In addition, in the selection phase 210, thetransmitter may monitor whether an object is present on an interfacesurface. When the transmitter detects that an object has been placed onthe interface surface, the transmitter may transition to the ping phase220 (S201). In the selection phase 210, the transmitter may transmit ananalogue ping signal of a very short pulse, and may detect whether theobject is present on the active area of the interface surface based onvariation in the current of a transmission coil.

When the presence of the object is detected, in the ping phase 220, thetransmitter activates a receiver, and transmits a digital ping signal toidentify whether the receiver has compatibility with the WPC standard.When the transmitter receives no response signal with respect to thedigital ping signal (e.g. a signal strength indicator) from the receiverin the ping phase 220, the transmitter may again transition to theselection phase 210 (S202). In addition, when the transmitter receives asignal that indicates the completion of power transfer (i.e. anend-of-charge signal) from the receiver in the ping phase 220, thetransmitter may also transition to the selection phase 210 (S203).

When the ping phase 220 is completed, the transmitter may transition tothe identification and configuration phase 230 for collectinginformation regarding the identification of the receiver and theconfiguration and state of the receiver (S204).

When the transmitter receives an unexpected packet or receives noexpected packet during a predefined time, when a packet transmissionerror occurs, or when no power transfer contract is set in theidentification and configuration phase 230, the transmitter maytransition to the selection phase 210 (S205).

When the identification and configuration for the receiver arecompleted, the transmitter may transition to the power transfer phase240 for wireless power transfer (S206).

When the transmitter receives an unexpected packet or receives noexpected packet during a predefined time (i.e. a time-out situation),when a violation of a preset power-transfer contract occurs, or whencharging ends in the power transmission phase 240, the transmitter maytransition to the selection phase 210 (S207).

In addition, the transmitter may transition from the power transferphase 240 to the identification and configuration phase 230 when it isrequired to reconfigure a power transfer contract depending on, forexample, variation in the state of the transmitter (S208).

The aforementioned power transfer contract may be set based oninformation regarding the states and properties of the transmitter andthe receiver. In one example, the transmitter state information mayinclude information regarding the maximum amount of power that may betransferred and the maximum number of receivers that the transmitter mayaccommodate, and the receiver state information may include informationregarding required power.

FIG. 3 is a state transition diagram for explaining a wireless powertransfer procedure that is defined in the PMA standard.

Referring to FIG. 3, power transfer from a transmitter to a receiverbased on the PMA standard may broadly be divided into a standby phase310, a digital ping phase 320, an identification phase 330, a powertransfer phase 340, and an end-of-charge phase 350.

A transmitter may transition to the standby phase 310 when a particularerror or a particular event is detected while a receiver identificationprocedure for power transfer is performed or while power transfer isunderway. Here, the particular error and the particular event willbecome apparent from the following description. In addition, in thestandby phase 310, the transmitter may monitor whether an object ispresent on a charge surface. When it is detected that an object has beenplaced on the charge surface or when an RXID retry is underway, thetransmitter may transition to the digital ping phase 320 (S301). Here,“RXID” is an inherent identifier assigned to a PMA-capable receiver. Inthe standby phase 310, the transmitter may transmit an analog pingsignal of a very short pulse, and may detect whether an object ispresent on the active area of the charge surface (e.g. a charger bed)based on variation in the current of a transmission coil.

The transmitter, having transitioned to the digital ping phase 320,transmits a digital ping signal for identifying whether the detectedobject is a PMA-capable receiver. When sufficient power is supplied to areception end by the digital ping signal transmitted by the transmitter,the receiver may modulate the received digital ping signal using a PMAcommunication protocol, thereby transmitting a predetermined responsesignal to the transmitter. Here, the response signal may include asignal strength indicator, which indicates the strength of powerreceived by the receiver. When receiving an available response signalfrom the receiver in the digital ping phase 320, the transmitter maytransition to the identification phase 330 (S302).

When no response signal is received, or when it is checked that theobject is not a PMA-capable receiver (i.e. a Foreign Object Detection(FOD) situation) in the digital ping phase 320, the transmitter maytransition to the standby phase 310 (S303). In one example, the ForeignObject (FO) may be a metallic object including, for example, a coin or akey.

In the identification phase 330, when a receiver identificationprocedure has failed or needs to be performed again, or when thereceiver identification procedure does not end within a predefined time,the transmitter may transition to the standby phase 310 (S304).

When receiver identification succeeds, the transmitter may transitionfrom the identification phase 330 to the power transfer phase 340 so asto initiate charging (S305).

In the power transfer phase 340, when the transmitter receives noexpected signal within a predetermined time (i.e. a time-out situation)or detects an FO, or when the voltage of a transmission coil exceeds apredefined reference value, the transmitter may transition to thestandby phase 310 (S306).

In addition, in the power transfer phase 340, when the temperaturesensed by a temperature sensor mounted in the transmitter exceeds apredetermined reference value, the transmitter may transition to theend-of-charge phase 350 (S307).

In the end-of-charge phase 350, when it is checked that the receiver isremoved from the charge surface, the transmitter may transition to thestandby phase 310 (S309).

In addition, when the temperature measured after a predetermined timehas passed becomes a reference value or less in an over-temperaturestate, the transmitter may transition from the end-of-charge phase 350to the digital ping phase 320 (S310).

In the digital ping phase 320 or the power transfer phase 340, thetransmitter may transition to the end-of-charge phase 350 when receivingan End of Charge (EOC) request from the receiver (S308 and S311).

FIG. 4 is a view for explaining an electromagnetic-induction-typewireless charging system according to an embodiment.

Referring to FIG. 4, the electromagnetic-induction-type wirelesscharging system includes a wireless power transmitter 400 and a wirelesspower receiver 450. The wireless power transmitter 400 and the wirelesspower receiver 450 are respectively substantially the same as thewireless power transmitter and the wireless power receiver describedwith reference to FIG. 1.

When an electronic appliance including the wireless power receiver 450is located on the wireless power transmitter 400, coils of the wirelesspower transmitter 400 and the wireless power receiver 450 may be coupledto each other by an electromagnetic field.

The wireless power transmitter 400 may modulate a power signal andchange a frequency in order to generate an electromagnetic field forpower transfer. The wireless power receiver 450 may receive power bydemodulating an electromagnetic signal depending on a protocol that isset so as to be suitable for a wireless communication environment, andmay transmit a predetermined feedback signal, which is used to controlthe strength of power to be transferred from the wireless powertransmitter 400 based on the strength of received power, to the wirelesspower transmitter 400 via in-band communication. In one example, thewireless power transmitter 400 may increase or reduce the amount ofpower to be transferred by controlling an operational frequency inresponse to a control signal for power control.

The amount of power to be transferred (or an increase/reduction in theamount of power) may be controlled using the feedback signal, which istransmitted from the wireless power receiver 450 to the wireless powertransmitter 400. In addition, communication between the wireless powerreceiver 450 and the wireless power transmitter 400 is not limited onlyto the aforementioned in-band communication using the feedback signal,but may be performed using out-of-band communication by a separatecommunication module. For example, a module for near-field wirelesscommunication, such as Bluetooth, Bluetooth Low Energy (BLE), NFC, orZigBee, may be used.

In electromagnetic induction, a frequency modulation method may be usedin a protocol for the exchange of state information and control signalsbetween the wireless power transmitter 400 and the wireless powerreceiver 450. Apparatus identification information, charging stateinformation, power control signals, and the like may be exchanged viathe protocol.

The wireless power transmitter 400 according to an embodiment, asillustrated in FIG. 4, may include a signal generator 420 for generatinga power signal, a coil L1 and capacitors C1 and C2, which are locatedbetween voltage supply ends V Bus and GND, which may sense the feedbacksignal transmitted from the wireless power receiver 450, and switchesSW1 and SW2, the operation of which is controlled by the signalgenerator 420. The signal generator 420 may include a demodulator 424for the demodulation of the feedback signal transmitted through the coilL1, a frequency drive unit 426 for frequency change, and a transmissioncontroller 422 for controlling the demodulator 424 and the frequencydrive unit 426. The feedback signal, transmitted through the coil L1, isdemodulated by the demodulator 424, and thereafter is input to thetransmission controller 422. The transmission controller 422 may controlthe frequency drive unit 426 based on the demodulated signal, therebychanging the frequency of the power signal to be transmitted to the coilL1.

The wireless power receiver 450 may include a modulator 452 fortransmitting the feedback signal through the coil L2, a rectifier 454for converting an Alternating Current (AC) signal, received through thecoil L2, into a Direct Current (DC) signal, and a reception controller460 for controlling the modulator 452 and the rectifier 454. Thereception controller 460 may include a voltage supply unit 462 forsupplying a voltage required for the operation of the rectifier 454 andother constituent elements of the wireless power receiver 450, a DC-DCtransformer 464 for changing a DC voltage output from the rectifier 454to a DC voltage that satisfies the charging requirement of a chargingobject (e.g., a load), the load 468 to which the converted voltage isoutput, and a feedback communication unit 466 for generating a feedbacksignal, which is used to provide the wireless power transmitter 400with, for example, information regarding the state of received power andthe state of the charging object.

In FIG. 4, although the coil L1, included in the wireless powertransmitter 400, means the three transmission coils 111, 112 and 113illustrated in FIG. 1, and the switches SW1 and SW2 and the capacitorsC1 and C2, connected to the transmission coils 111, 112 and 113, may beprovided on each transmission coil 111, 112 or 113, the scope of thedisclosure is not limited thereto.

FIG. 5 is a view for explaining the configuration of a transmission coilaccording to an embodiment.

Referring to FIG. 5, a transmission coil module 500 refers to a modulardevice in which the coil L1 illustrated in FIG. 4 may be mounted so asto be connected to a control circuit board, which includes elements forcontrolling the operation of the wireless power transmitter 400, suchas, for example, the switches SW1 and SW2 and the signal generator 420.The coil mounted in the transmission coil module 500 may include thethree transmission coils 111, 112 and 113 illustrated in FIG. 1.

The coils mounted in the transmission coil module 500 may have variousstandards (e.g. a certified coil based on the WPC standard or acertified coil based on the PMA standard). The shape, size, temperatureproperty, power transfer efficiency, connection property, and the likeof coils having various standards may differ between the standards.Accordingly, the transmission coil module 500 may be manufactured so asto be customizable to suit target coils among coils having variousstandards.

Although a method of manufacturing the transmission coil module 500 suchthat three coils may be mounted to overlap each other is described inthis specification, the scope of the disclosure is not limited thereto.An arbitrary number of coils (e.g. one coil or four coils) may bearranged at arbitrary positions.

The transmission coil module 500 may include a top coil 510, a coilframe 520, first and second bottom coils 530-1 and 530-2, a shield 540,a metal sheet 550, and a connector 560.

The top coil 510 may correspond to any one of the three transmissioncoils 111, 112 and 113 illustrated in FIG. 1 (e.g. the transmission coil112). The top coil 510 may be implemented in the form of a spirallywound electric wire, and the cross section of the electric wire mayinclude a conductive material (e.g. copper (Cu)) and an insulatingmaterial surrounding the conductive material.

The coil frame 520 may provide a frame on which other elements of thetransmission coil module 500, including the top coil 510 and the firstand second bottom coils 530-1 and 530-2, may be mounted. Although thecoil frame 520 may be formed of reinforced plastic, the scope of thedisclosure is not limited thereto. When the coil frame 520 is formed ofreinforced plastic, the coils 510, 530-1 and 530-2 may be protected fromexternal shocks and damage, and the overall weight of the transmissioncoil module 500 may be reduced.

Each of the first and second bottom coils 530-1 and 530-2 may correspondto any one of the three transmission coils 111, 112 and 113 illustratedin FIG. 1 (e.g. the transmission coil 111 or 113). Each of the first andsecond bottom coils 530-1 and 530-2 may be implemented in the form of aspirally wound electric wire, and the cross section of the electric wiremay include a conductive material (e.g. copper (Cu)) and an insulatingmaterial surrounding the conductive material.

The first and second bottom coils 530-1 to 530-2 may overlap the topcoil 510 so as to prevent the generation of a dead spot in whichcharging is impossible as the result of areas in which wireless chargingis possible being completely separated from each other, and may bespaced apart from each other in the same plane.

The shield 540 may shield a magnetic field generated in the coils 510,530-1 and 530-2, thereby preventing the magnetic field from beingtransferred to the external control circuit board. Although the shield540 may be configured as a ferrite sheet, the scope of the disclosure isnot limited thereto.

The metal sheet 550 may function as a radiator, which may maintain theshape of the transmission coil module 500 and may dissipate the heatgenerated in the coils to the outside. Although the metal sheet 550 maybe formed of aluminum (Al), the scope of the disclosure is not limitedthereto.

The shield 540 and the metal sheet 550 may be placed inside the coilframe 520.

The connector 560 may allow the coils 510, 530-1 and 530-2 to beconnected to the external control circuit board through the coil frame520.

In this specification, “top” may refer to the side closer to aninterface surface on which a wireless power receiver may be placed.

FIGS. 6 to 10 are views respectively for explaining a method ofmanufacturing the transmission coil module according to an embodiment.

Referring to FIGS. 6 to 10, in a first step S10, the top coil 510 may beinserted into the space in the coil frame 520 that corresponds to thetop coil 510.

Prior to describing the insertion process, the detailed configuration ofthe coil frame 520 will first be described.

The coil frame 520 may include a fixing hole 521, support plates 522-1to 522-3, central fixing plates 523-1 to 523-3, functional holes 524-1to 524-3, and a lead wire insertion terminal 525.

The coil frame 520 may provide a first receptacle, into which onetransmission coil 510 may be inserted, in the upper region thereof, anda second receptacle and a third receptacle, into which the twotransmission coils 530-1 and 530-2 may be respectively inserted, in thelower region thereof. Each of the first receptacle, the secondreceptacle, and the third receptacle may overlap each other in at leasta portion thereof. The scope of the disclosure is not limited thereto.The coil frame 520 may be formed such that two transmission coils areinserted into the upper region thereof and one transmission coil isinserted into the lower region thereof.

The first receptacle includes the area that overlaps each of the secondreceptacle and the third receptacle, and the overlapping area may be 50%or more of the entire area of the first receptacle.

The fixing hole 521 is formed such that a fixing member (e.g. a bolt ora nut) for fastening with another element of the wireless powertransmitter (e.g. the control circuit board) is inserted into the fixinghole 521. That is, the transmission coil module 500 may be fastened toanother element using the fixing hole 521 after the manufacturingprocess illustrated in FIGS. 6 to 10 is completed.

The support plates 522-1 to 522-3 may support the coils 510, 530-1 and530-2 and may provide the space, into which the coils 500, 530-1 and530-2 may be inserted, depending on the outer contour and size of thecoils 510, 530-1 and 530-2.

That is, the support plate 522-1 supports the top coil 510, and providesthe space into which the first and second bottom coils 530-1 and 530-2may be inserted. The support plate 522-2 supports the first bottom coil530-1, and provides the space into which the top coil 510 and the firstbottom coil 530-1 may be inserted. In addition, the support plate 522-3supports the second bottom coil 530-2, and provides the space into whichthe top coil 510 and the second bottom coil 530-2 may be inserted.

The support plates 522-1 to 522-3 may collectively be called a supportunit. The support unit may surround the first, second and thirdreceptacles. The central fixing plates 523-1 to 523-3 may provide thespace, into which the coils 510, 530-1 and 530-2 may be inserted,depending on the inner shape and size of the coils 510, 530-1 and 530-2.That is, each of the central fixing plates 523-1 to 523-3 may have ashape corresponding to the inner shape of each of the coils 510, 530-1and 530-2.

A portion of each of a second central fixing plate 523-2 and a thirdcentral fixing plate 523-3 may overall the first receptacle. Inaddition, a portion of a first central fixing plate 523-1 may overlapthe second receptacle and the third receptacle.

The support plates 522-1 to 522-3 and the central fixing plates 523-1 to523-3 may be realized such that the coils 510, 530-1 and 530-2 are fixedthereto so as not to come into contact with one another. In addition,the support plates 522-1 to 522-3, i.e. the support unit, and thecentral fixing plates 523-1 to 523-3 may be integrally formed with eachother.

The upper surface of the central fixing plate 523-1 may be located atthe same height as the upper surfaces of the support plates 522-2 and522-3, and the central fixing plate 523-1 may have the same thickness asthe top coil 510. In addition, the upper surface of the support plate522-1 may be located at the same height as the lower surface of thecentral fixing plate 523-1, and may provide a space in which the topcoil 510 may be seated and fixed.

In the same manner, the lower surfaces of the central fixing plates523-2 and 523-3 may be at the same height as the lower surface of thesupport plate 522-1, and the central fixing plates 523-2 and 523-3 mayhave the same thickness as the first and second bottom coils 530-1 and530-2. In addition, the lower surfaces of the support plates 522-2 and522-3 may be at the same height as the upper surfaces of the centralfixing plates 523-2 and 523-3, and may provide a space in which thefirst and second bottom coils 530-1 and 530-2 may be seated and fixed.

The scope of the disclosure is not limited to the above description, andthe coil frame 520 may additionally provide an extra space in which leadwires of the coils 510, 530-1 and 530-2 are connected to the lead wireinsertion terminal 525.

Although a method using a separate adhesive sheet (e.g. a piece ofdouble-sided tape) or a method of applying a synthetic resin havingadhesive and insulating properties (e.g. a bonding method) may be usedwhen the top coil 510 is inserted into the coil frame 520, the scope ofthe disclosure is not limited thereto.

The functional holes 524-1 to 524-3 may be provided to acquireadditional information related to the coils 510, 530-1 and 530-2. Forexample, a thermistor, which outputs an electrical signal correspondingto the temperature of each of the coils 510, 530-1 and 530-2, may beincluded in the control circuit board below the functional holes. Eachthermistor may sense the temperature of a corresponding one of the coils510, 530-1 or 530-2 through the functional holes 524-1 to 524-3.

In another embodiment, the functional holes 524-1 to 524-3 may beomitted.

The lead wire insertion terminal 525 may be provided such that all sixlead wires of the coils 510, 530-1 and 530-2 may be fitted. Each of thespiral coils 510, 530-1 and 530-2 may be provided on the inner end andthe outer end thereof with respective lead wires. The lead wires maycorrespond to both ends of the coil L1 illustrated in FIG. 4, and may beconnected to the control circuit board through the connector 560.

Referring to FIG. 7, in a second step S20, the first and second bottomcoils 530-1 and 530-2 may be inserted into the respective spacescorresponding thereto in a coil frame 520 a on which the top coil 510has been mounted.

In another embodiment, the second step S20 may be performed before thefirst step S10.

Although a method using a separate adhesive sheet (e.g. a piece ofdouble-sided tape) or a method of applying a synthetic resin havingadhesive and insulating properties (e.g. a bonding method) may be usedwhen the first and second bottom coils 530-1 and 530-2 are inserted intothe coil frame 520 a, the scope of the disclosure is not limitedthereto.

Referring to FIG. 8, in a third step S30, the shield 540 may be attachedto the space corresponding thereto in the lower region of a coil frame520 b on which the first and second bottom coils 530-1 and 530-2 havealso been mounted. The shield 540 may be formed to have an area andshape that correspond to the area and shape of the plane in which thecoils 510, 530-1 and 530-2 are arranged. For example, the shield 540 mayhave a slightly greater area than the area of the plane in which thecoils 510, 530-1 and 530-2 are arranged, and may have a shape similar tothe shape of the plane. This is because the shield 540 functions toblock a magnetic field emitted from the coils 510, 530-1 and 530-2.

Although a method using a separate adhesive sheet (e.g. a piece ofdouble-sided tape may be used when the shield 540 is attached to thecoil frame 520 b, the scope of the disclosure is not limited thereto.

In addition, the shield 540 may be provided with functional holes 541-1to 541-3, which are located so as to correspond to the functional holes524-1 to 524-3 described with reference to FIG. 6 and have the samefunction as the functional holes 524-1 to 524-3.

Referring to FIG. 9, in a fourth step S40, the metal sheet 550 may beattached to the space corresponding thereto in the lower region of acoil frame 520 c on which the shield 540 has also been mounted. Themetal sheet 550 may be formed to have the same area and shape as aplanar area of the coil frame 520 excluding the fixing hole 521 and thearea for attachment of the connector 560.

Although a method using a separate adhesive sheet (e.g. a piece ofdouble-sided tape may be used when the metal sheet 550 is attached tothe coil frame 520 c, the scope of the disclosure is not limitedthereto.

In addition, the metal sheet 550 may be provided with functional holes551-1 to 551-3, which are located so as to correspond to the functionalholes 524-1 to 524-3 described with reference to FIG. 6 and have thesame function as the functional holes 524-1 to 524-3.

Referring to FIG. 10, in a fifth step S50, the connector 560 may beattached to the space corresponding thereto in the lower region of acoil frame 520 d on which the metal sheet 550 has also been mounted. Theplanar area of the connector 560 may be the same as the area of themetal sheet 550 for attachment of the connector 560.

One side surface of the coil frame 520 may be indented (or recessed),and the connector 560 may be located in the indented side surface. Inaddition, the lead wire insertion terminal 525 is also formed on theindented side surface.

The inner portion of the connector 560 may be attached to the bottom ofthe coil frame 520 d, and the outer portion of the connector 560 mayinclude an upper terminal 561 and a lower terminal 562.

The inner portion of the connector 560 may be attached to the coil frame520 d so as to overlap at least a portion of the lead wire insertionterminal 525. Thereby, lead wires of the coils 510, 530-1 and 530-2fitted into the lead wire insertion terminal 525 may be fixed.

The upper terminal 561 of the connector 560 may be connected to the leadwires of the respective coils 510, 530-1 and 530-2 mounted on the coilframe 520, and the lower terminal 562 of the connector 560 may beconnected to a corresponding terminal of the control circuit board.Specifically, the upper terminal 561 and the lower terminal 562 of theconnector 560 may include twelve pins. All six lead wires of the coils510, 530-1 and 530-2 may be connected respectively to two pins locatedat corresponding positions, among the twelve pins. Accordingly, amongthe twelve pins of the lower terminal 562, two respective adjacent pinsmay be connected to any one of the six lead wires so that the coils 510,530-1 and 530-2 are connected to the control circuit board.

At this time, although connection between the two pins and the lead wiremay be performed via soldering using a laser, the scope of thedisclosure is not limited thereto.

In addition, although a method using a separate adhesive sheet (e.g. apiece of double-sided tape) may be used when the connector 560 isattached to the coil frame 520 d, the scope of the disclosure is notlimited thereto.

The effects of the transmission coil module according to the embodimentswill be described below.

With the transmission coil module according to the embodiments, atransmission coil device having optimum functionality may bemanufactured using only a simplified process of inserting acorresponding coil into a coil frame having an optimum modular structureand attaching it thereto.

In addition, through the modularization of coils, a transmission coilmodule, which may be applied without change to various applications(e.g. a wireless power transmitter for vehicles or a wireless powertransmitter for charging a mobile phone), may be provided.

In addition, although various standards pertaining to transmission coilsexist, as the result of providing a coil frame optimized to a coilhaving a corresponding standard, when a wireless power transmitter usinga coil satisfying a particular standard is manufactured, a coil framecorresponding to the particular standard may be used, which may reducedesign costs and the amount of time required for the arrangement ofcoils, etc.

The effects to be accomplished by the embodiments are not limited to theaforementioned effects, and other unmentioned effects will be clearlyunderstood from the above description by those having ordinary skill inthe art.

The method according to the above-described embodiment may beimplemented as a program that is to be executed in a computer and may bestored in a computer-readable recording medium, and examples of thecomputer-readable recording medium may include a ROM, a RAM, a CD-ROM, amagnetic tape, a floppy disc, and an optical data storage device. Inaddition, the computer readable recording medium is implemented in acarrier wave (e.g., data transmission over the Internet).

The computer-readable recording medium may be distributed in a computersystem connected thereto via a network so that a computer-readable codemay be stored and executed in a distributed manner. In addition,functional programs, codes, and code segments for realizing theabove-described method may be easily deduced by programmers skilled inthe art related to the embodiment.

It will be clearly understood by those skilled in the art that theembodiments may be realized in other particular forms within a rangethat does not deviate from the spirit and essential features of theembodiments.

Accordingly, the above detailed description should not be construed asbeing limited in all terms, but should be considered to be exemplary.The scope of the embodiments should be determined by the reasonableinterpretation of the accompanying claims, and all changes that fallwithin the range equivalent to the embodiments should be understood asbelonging to the scope of the embodiments.

What is claimed is:
 1. A transmission coil module for wirelesslytransmitting power, the transmitting coil module comprising: at leastone transmission coil having a hollow portion in a center area thereof;a shield disposed below the at least one transmission coil; and a metalsheet disposed below the shield, wherein the at least one transmissioncoil includes: a top coil disposed at an upper portion and having ahollow portion in a center area thereof; a first bottom coil disposedbelow the top coil and having a hollow portion in a center area thereof;and a second bottom coil disposed below the top coil and having a hollowportion in a center area thereof, wherein the top coil overlaps aportion of each of the first bottom coil and the second bottom coil, andwherein the shield includes a first functional hole in a regioncorresponding to the hollow portion of the first bottom coil, a secondfunctional hole in a region corresponding to the hollow portion of thetop bottom coil, and a third functional hole in a region correspondingto the hollow portion of the second bottom coil.
 2. The transmissioncoil module according to claim 1, wherein the metal sheet includesaluminum (Al).
 3. The transmission coil module according to claim 1,wherein the shield is a ferrite sheet.
 4. The transmission coil moduleaccording to claim 1, wherein the first bottom coil is spaced apart fromthe second bottom coil in a same plane.
 5. The transmission coil moduleaccording to claim 1, wherein the at least one transmission coilincludes a spirally wound electric wire, and a cross section of theelectric wire includes a conductive material and an insulating materialsurrounding the conductive material.
 6. The transmission coil moduleaccording to claim 1, wherein the shield is configured to shield amagnetic field generated in the at least one transmission coil andprevent the magnetic field from being transferred to an external controlcircuit board.
 7. The transmission coil module according to claim 1,wherein the metal sheet corresponds to a heat sink.
 8. The transmissioncoil module according to claim 1, wherein the at least one of the first,second and third functional hole in the shield receives a thermistor tosense temperature information of the at least one transmission coil. 9.The transmission coil module according to claim 8, further comprising: aprinted circuit board below the metal sheet, wherein the thermistor ison the printed circuit board and senses the temperature information ofthe at least one transmission coil.
 10. A transmission coil module forwirelessly transmitting power, the transmission coil module comprising:a plurality of transmission coils comprising a first transmission coiland a second transmission coil disposed below the first transmissioncoil; a coil frame including a first receptacle formed on a firstsurface of the coil frame and configured to receive the firsttransmission coil and a second receptacle formed on a second surface ofthe coil frame that is opposite to the first surface and configured toreceive the second transmission coil; a shield disposed below the firsttransmission coil and the second transmission coil; a metal sheetdisposed below the shield, wherein the coil frame further includes atleast one fixing hole on a rim side thereof to receive a fixing member.11. The transmission coil module according to claim 10, wherein thefirst receptacle and the second receptacle have a same depth as athickness of the first transmission coil and the second transmissioncoil.
 12. The transmission coil module according to claim 10, wherein aportion of the first receptacle and a portion of the second receptacleoverlap each other.
 13. The transmission coil module according to claim10, wherein the first transmission coil and the second transmission coiloverlap each other at an overlapping portion.
 14. The transmission coilmodule according to claim 13, wherein the first transmission coil in thefirst receptacle and the second transmission coil in the secondreceptacle contact each other at the overlapping portion.
 15. Thetransmission coil module according to claim 13, wherein some of theoverlapping portion is formed to penetrate the coil frame such that apart of the first transmission coil disposed in the first receptacle anda part of the second transmission coil disposed in the second receptacledirectly contact with each other.
 16. The transmission coil moduleaccording to claim 10, wherein the first receptacle includes a firstcentral fixing plate at a central portion of the first receptacle, andthe second receptacle includes a second central fixing plate at acentral portion of the second receptacle, and wherein the first centralfixing plate of the first receptacle is disposed at a positioncorresponding to a hollow portion of the first transmission coil, andthe second central fixing plate of the second receptacle is disposed ata position corresponding to a hollow portion of the second transmissioncoil.
 17. The transmission coil module according to claim 16, wherein apart of the first central fixing plate of the first receptacle directlycontacts a part of the second transmission coil disposed in the secondreceptacle and supports the part of the second transmission coildisposed in the second receptacle, and wherein a part of second centralfixing plate formed in the second receptacle directly contacts a part ofthe first transmission coil disposed in the first receptacle to supportthe part of the first transmission coil disposed in the firstreceptacle.
 18. The transmission coil module according to claim 10,wherein the coil frame includes reinforced plastic.
 19. The transmissioncoil module according to claim 10, further comprising: a thirdtransmission coil disposed below the first transmission coil, whereinthe coil frame further includes a third receptacle formed on the secondsurface of the coil frame and configured to receive the thirdtransmission coil.